A war of words between prominent NATO members over its continued existence has revealed cracks in the 70-year-old alliance, which seems to be returning to its Cold War roots in desperate search for a new sense of purpose.

"The transatlantic relationship is in a very, very healthy place," insisted US officials briefing reporters on the eve of the NATO summit in London. Meanwhile, Secretary-General Jens Stoltenberg has been repeating that NATO is the "most successful alliance in history."

Behind this brave facade, however, the septuagenarian alliance is tearing itself apart. US President Donald Trump's insistence on everyone dedicating two percent of their GDP to military spending is a target only seven members have met so far. Most NATO countries are nothing but hangers-on to the US military, and can't conduct independent operations. Only a few, like Turkey, can - and the fact that Ankara just did, without bothering to consult the rest of the alliance, is the cause for the latest display of discord.

French President Emmanuel Macron set things off by complaining about Ankara's operation in Syria last month, pointing to "no coordination whatsoever" between either the US or Turkey with the rest of NATO and calling the alliance "brain dead."

That, ironically, brought otherwise feuding NATO members together - in condemnation of the French leader. Turkish President Recep Tayyip Erdogan tore into Macron on Friday, suggesting he should have "his own brain death checked."

He also accused Macron of being ignorant about fighting terrorism and eager to "show off" but not to "properly pay for NATO." Neither Turkey nor France are currently meeting the two percent quota. Paris responded by summoning the Turkish ambassador to protest the "insults."

Erdogan's verbal volley comes amid reports that Turkey has been holding hostage NATO's military plans for Poland and the Baltic states, demanding support for its operations in Syria against the US-allied Kurdish militias.

In addition to ignoring NATO, Ankara's 'Operation Peace Spring' ran roughshod over Washington's concerns as well. Erdogan outright ignored a very bluntly-worded letter from Trump, and only halted the invasion after Russian and Syrian troops secured the border once patrolled by US forces.

Turkey's growing military and economic ties with Russia - from the TurkStream gas pipeline to the purchase of S-400 air defense systems - have also put Ankara on Washington's naughty list, as the US and NATO establishments have been busily reviving the Cold War demonization of Moscow. Erdogan doesn't seem to care, knowing that NATO has no method for expelling members and, apparently, counting on Turkey's strategic importance outweighing any US concerns in the long run.

German MP Alexander Neu isn't so sure that this will be the case forever. He tells RT that Turkey is pursuing policies that "Washington will bring to an end sooner or later." Erdogan seems to be building a new Ottoman Empire, but lacks economic resources needed for such imperial ambitions, and some of his policies are "at least unclear, very often even extremely destructive," said Neu, who represents the leftist Die Linke in the Bundestag.

Meanwhile, Berlin has emerged as Ankara's unexpected ally in the spat with Paris. Chancellor Angela Merkel's reaction to the French president's remarks was to scold him like an errant schoolboy.

"Over and over, I have to glue together the cups you have broken so that we can then sit down and have a cup of tea together," Merkel told Macron matronly, saying she was "tired of picking up the pieces."

With Merkel looking forward to retiring in 2021, her ruling coalition does not appear the least bit interested in rocking the NATO boat. Germany prefers to rely on the US and NATO for its security, according to Gerhard Mangott, political science professor at the Innsbruck University in Austria.

"The French position, that the strategic autonomy of Europe needs to be strengthened, does not have much backing among the NATO allies," Mangott told RT, adding that most of them still regard the US as "indispensable."

This seems to sit just fine with the Washington establishment, which regards the relationship with its European vassals as something that's not up for debate. Trump dared to question the alliance on the campaign trail, but has since been persuaded to settle for greater financial burden-sharing by the Europeans. His top diplomat, however, seems to have a far more ambitious vision.

At the recent ministerial meeting in Brussels, US Secretary of State Mike Pompeo pointedly said that NATO should "address the current and potential long-term threat posed by the Chinese Communist Party." While that may be a return to the alliance's Cold War roots, it also sets its sights on the opposite side of the planet - nowhere near the North Atlantic. Then again, neither is Afghanistan, where NATO has been "assisting" the US since 2001.

Both Macron's criticism of continental (in)capabilities and Trump's burden-sharing objections are attempts to treat the symptoms rather than the underlying problem, argues Jan Oberg, director of the Sweden-based Transnational Foundation for Peace and Future Research.

"There's nobody who has a vision about how Europe or the Western world should defend itself against the challenges we're headed for," Oberg told RT. Most of these challenges are not military in nature, he added, but NATO insists on military solutions because that is the only approach it has ever known.

Cold War histories written by the victors depict NATO as a purely defensive alliance created in response to the "aggressive" Soviet Union. They generally gloss over the fact that the Warsaw Pact was founded six years after NATO, and both it and the Soviet Union dissolved at the end of the conflict - while US troops stayed in Europe and drove NATO expansion eastward.

Lord Hastings Ismay, NATO's first secretary-general, famously described the alliance's purpose as "to keep the Russians out, the Americans in, and the Germans down."In that respect at least, NATO has been a success - whatever else it has done over the past seventy years.

Today, however, Oberg believes NATO is "a dinosaur that's outlived its purpose." Neu, the German MP, thinks that "only a new collective security system, including Russia, can liberate us from this desolate and dangerous situation in Europe."

Scare-mongering about Russia, China, terrorism or something else amounts to excuses, not reasons, for NATO's continued existence. The alliance's defenders can't exactly say out loud that it all boils down to decades of bureaucratic inertia and a captive market for the military-industrial complex. Maybe that is why they lash out at anyone who dares ask the inconvenient questions.

Were Johnson to lose to Labour's Jeremy Corbyn, that would give NATO yet another individual to worry about at its next summit, due in 2021.

Over his career the socialist firebrand has called NATO "a danger to world peace and a danger to world security". He has more recently fallen into line with party policy, which is for the U.K. to stay in the alliance, but he'd likely prove another awkward partner.

The last time Britain hosted NATO leaders, in 2014, he told an anti-NATO rally the end of the Cold War "should have been the time for NATO to shut up shop, give up, go home and go away."